1. Field of the Invention
The present invention relates to a method for executing three-dimensional measurement processing on a range where viewing fields of a plurality of cameras overlap by using images produced with the plurality of cameras, and a three-dimensional measuring apparatus for executing the method.
2. Description of Related Art
In three-dimensional measurement processing based upon the binocular vision principle, images of an object to be measured are picked up with each of two cameras or more from different directions, and respective feature points on the produced images which represent an identical image are corresponded to each other. A coordinate of the feature point extracted from each of the images is substituted into an operational expression to calculate a three-dimensional coordinate (refer to, for example, Japanese Patent Application Laid-Open No. 2002-99902).
Performing the measurement processing as shown in Japanese Patent Application Laid-Open No. 2002-99902 above requires inclusion of each point to be measured in viewing fields of all cameras. This necessitates adjustment of a positional relation among each of the cameras based upon a range where the object to be measured is included or a height range that the measuring object can take to secure the accuracy of three-dimensional measurement.
However, it is highly difficult to recognize the range or the height range where viewing fields of all the cameras overlap. Especially in a case where the apparatus is used by a user lacking expertise on three-dimensional measurement, the user adjusts cameras by trial and error without knowing how to adjust the cameras, thereby to come into a state suitable for measurement. Hence the adjustment operation can be time and labor consuming.